使用Kaptcha 生成验证码十分简单并且参数可以进行自定义，以下简单记录下使用步骤。
1.在pom.xml中添加maven依赖：
<dependency> <groupId>com.google.code.kaptcha</groupId> <artifactId>kaptcha</artifactId> <version>2.3</version> <classifier>jdk15</classifier> </dependency>
2.web.xml中配置kaptcha属性：
<bean id="verifyCodeProducer" class="com.google.code.kaptcha.impl.DefaultKaptcha">
<property name="config">
<bean class="com.google.code.kaptcha.util.Config">
<constructor-arg>
<props>
<prop key="kaptcha.border">yes</prop>
<prop key="kaptcha.border.color">105,179,90</prop>
<prop key="kaptcha.border.thickness">1</prop>
<prop key="kaptcha.noise.color">blue</prop>
<prop key="kaptcha.image.width">150</prop>
<prop key="kaptcha.image.height">50</prop>
<prop key="kaptcha.session.key">verifyCode</prop>
<!-- <prop key="kaptcha.textproducer.char.string">0123456789abcdefghijklmnopqrst!@#$%^*</prop> -->
<prop key="kaptcha.textproducer.char.length">4</prop>
<prop key="kaptcha.textproducer.char.space">4</prop>
<prop key="kaptcha.textproducer.font.size">30</prop>
<prop key="kaptcha.textproducer.font.color">blue</prop>
</props>
</constructor-arg>
</bean>
</property>
</bean>
其中bean节点的id值 verifyCodeProducer 为在类中引用@Resource生成实例时的名称；属性配置中 kaptcha.session.key 的值为在session中存取名称。
在servlet节点中配置
3.controller类中的相关方法：
@Controller
public class CommonController {
@Autowired
private Producer verifyCodeProducer;
@RequestMapping(path = "/getVerifyCodeImage", method = RequestMethod.GET)
public void getVerifyCodeImage(HttpServletRequest request, HttpServletResponse response) {
HttpSession session = request.getSession();
ResponseUtils.noCache(response);
response.setContentType("image/jpeg");
String capText = verifyCodeProducer.createText();
session.setAttribute(Constants.SESSION_KEY_VERIFY_CODE, capText);
BufferedImage bi = verifyCodeProducer.createImage(capText);
ServletOutputStream out = null;
try {
out = response.getOutputStream();
ImageIO.write(bi, "jpg", out);
out.flush();
} catch (Exception ex) {
LOGGER.error("Failed to produce the verify code image: ", ex);
throw new ServerInternalException("Cannot produce the verify code image.");
} finally {
IOUtils.closeQuietly(out);
}
}
}
Constants.SESSION_KEY_VERIFY_CODE为属性配置中 kaptcha.session.key 的值。
4.jsp：
<div class="form-group has-feedback">
<span class="glyphicon glyphicon-barcode form-control-feedback"></span>
<input id="verifyCode" name="verifyCode" type="text" maxlength="4" class="form-control" placeholder="<spring:message code='login.label.code' />" />
<div style="height: 1px"></div>
<img src="${pageContext.request.contextPath}/getVerifyCodeImage" id="verifyCodeImage" style="margin-bottom: -3px" />
<a href="#" rel="external nofollow" onclick="changeVerifyCode()"><spring:message code='login.code.tip' /></a>
</div>
function changeVerifyCode() {
$('#verifyCodeImage').hide().attr('src', '${pageContext.request.contextPath}/getVerifyCodeImage?' + Math.floor(Math.random()*100) ).fadeIn();
event.cancelBubble=true;
}
5.kaptcha属性说明：
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。
